The firearms training industry has, for a number of years, trained individuals in the use of firearms by using systems that incorporate simulated weapons and simulated scenarios. Typically, these systems present a trainee with simulated situations which require the trainee to exercise judgment in determining when and where to fire a simulated weapon. The simulated situations are typically produced as an interactive cinematic environment using videotaped situations with actual people and locations to create a realistic environment for the trainee. Throughout the cinematic experience, the systems detect and record the location of each “shot” fired by the trainee in relation to the position of the character to which the shot was directed.
In such systems, the detection and location of a trainee's shot is often accomplished through use of a simulated weapon that works in conjunction with data acquisition equipment. The simulated weapon and data acquisition equipment may take on various forms. For example, in one weapons training system, the simulated weapon may employ a laser light source to generate a spot on the screen (or reflective surface) when the weapon is aimed and fired by the trainee. The data acquisition equipment employs an area array image sensor, such as a Charge Coupled Device (CCD) camera, to detect and locate the position of the laser spot when it is directed upon the screen by the trainee.
To accomplish these tasks, the CCD camera is aimed at the screen to constantly receive an updated image consisting of light reflected from the screen. Before entering the CCD camera, the reflected light passes through a filter that prevents passage of all light not having a wavelength equal to that of the laser light. Thus, only reflected light from the laser spot actually enters the CCD camera where it is imposed on a sensor surface comprised of individual CCD sensors arranged in a two-dimensional array (or row and column grid) like the discrete pixels on a computer monitor or television screen. When struck by the reflected light of the laser spot, the sensors produce an electrical signal corresponding to the intensity of the light received by the sensors. By scanning all of the sensors in the sensor array one row after another, the current image received by the CCD camera is converted into a plurality of discrete electrical signals or pixels. The presence and location of a laser spot is determined by subsequent analysis of the acquired pixel data.
Other firearms training systems enable multiple individuals to be trained simultaneously as a team using similar simulated weapons and data acquisition equipment. To detect and distinguish between multiple weapons that may be fired at the same time by multiple trainees, some systems employ simulated weapons having a laser light source which is modulated at a preset frequency. By modulating the lasers of the different weapons in the system at different preset frequencies, appropriate data acquisition equipment is able to distinguish a laser spot generated by one weapon from the laser spots generated by the other weapons.
Various patents disclose the use of laser or other light energy with firearms to simulate firearm operation. For example, U.S. Pat. No. 3,633,285 discloses a laser transmitting device for marksmanship training. The device is readily mountable to the barrel of a firearm, such as a rifle, and transmits a light beam upon actuation of the firearm firing mechanism. The laser device is triggered in response to an acoustical transducer detecting sound energy developed by the firing mechanism. The light beam is detected by a target having a plurality of light detectors, whereby an indication of aim accuracy may be obtained.
Another patent, U.S. Pat. No. 3,938,262, discloses a laser weapon simulator that utilizes a laser transmitter in combination with a rifle to teach marksmanship by firing laser bullets at a target equipped with an infrared detector. The laser weapon includes a piezoelectric crystal coupled to a laser disposed in a housing for mounting axially to a rifle barrel. The rifle may develop a mechanical force by firing a blank cartridge which generates a shock wave and vibrates the piezoelectric device.
Finally, U.S. Pat. No. 3,995,376 discloses a miniaturized laser apparatus mounted on a weapon, where the power source and circuitry for the laser apparatus are contained within the weapon. The laser weapon is fired in a normal manner by squeezing the trigger while aiming at a target.
In each of these training systems, where lasers are used to measure the accuracy of the shooter, is it important that the laser light source be properly aligned with the direction of the barrel of the weapon simulator so that the laser will follow the same path as a projectile of an actual firearm. This is problematic, in that even when the light source is properly aligned in the barrel initially, the laser light source may drift or move within the barrel during operation of the firearm, and create an inaccurate result. Specifically, recoil in the firearm can sometimes create movement in the laser light source that misaligns the laser light from the projected path of fired ammunition. Thus, when the laser is misaligned with the direction of the barrel of the weapon simulator, inaccurate results are obtained.
In attempting to prevent movement of the laser light source within the firearm barrel, several solutions have been proposed. One such solution includes the application of an adhesive material to the laser light source to keep it secure within or to the firearm barrel. A problem with such a solution is that the use of adhesive materials could cause the laser light source to receive the full impact of recoil of the firearm, which would lead to the premature failure of that laser light source. In addition, the adhesive materials would prevent or substantially hinder the removal of the laser light source from the barrel of the firearm, such that repair or improvements to the firearm would be difficult.